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Picked up a GMC 7500 with a C7 CAT VIN# KAL77538, they did…

picked up a GMC 7500...
picked up a GMC 7500 with a C7 CAT VIN# ***** they did one piston and liner, re ringed the other 5 and put used injectors in... truck smokes whitish grey, smells like diesel to the point it burns your eyes inside shop and won't get over 1500 RPM's... no codes and did an injector cut out test with no significant difference..... need a direction on ehere to go next
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Answered in 5 minutes by:
7/9/2018
Technician: Cat Man, Cat Engine Expert replied 4 years ago
Cat Man
Cat Man, Cat Engine Expert
Category: Medium and Heavy Trucks
Satisfied Customers: 10,344
Experience: I am ASE Master Truck Certified.
Verified
Thanks for asking your question. I will try and help you out.
Has the fuel pressure been checked?
Also. Has the inlet air filter and turbo been checked?
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Customer reply replied 4 years ago
ok... problem with RPM's was PTO switch was bad fooling computer into keeping RPM low... still smoking like hell and strong fuel smell....I'm going to try and put a new set of injectors in,,, do they need to be flashed
Technician: Cat Man, Cat Engine Expert replied 4 years ago
10-4.
Yes they have trim files on the new ones that need to be installed.
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Customer reply replied 4 years ago
can that be done with a Bosch DCU100 diagnostic tool
Technician: Cat Man, Cat Engine Expert replied 4 years ago
Unfortunately not. It can only be done with Cat ET. Sorry.
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Customer reply replied 4 years ago
will the truck run if they aren't flashed? Talked to someone yesterday that said he put a set in a C15 and never flashed them
Technician: Cat Man, Cat Engine Expert replied 4 years ago
it will run and not hurt anything. Just may run rough.
The early C15 has trim codes. The later C15 have trim files.
Cat Man
Cat Man, Cat Engine Expert
Category: Medium and Heavy Trucks
Satisfied Customers: 10,344
Experience: I am ASE Master Truck Certified.
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